1. Field of the Invention
The present invention relates to a ball joint utilizing a ball to connect two links so as to be relatively rotatable and tiltable.
2. Description of the Prior Art
As shown by FIG. 7 of the accompanying drawings, the typical ball joint of prior art is constructed by welding a rod b to a metal housing a, a spherical portion e of a ball stud d with a ball seat c made of synthetic resin, fitting this spherical portion e into the housing a, then caulking a bottom lid I to the housing a, thereafter inserting a lower end of a duet boot f into a groove h formed around the housing a and fixing this dust boot f by with a ring boot g. In view of such construction, relatively many parts required by the ball joint of prior art increase cost of parts as well as cost for assembling these parts and particularly the metal housing of complicated shape further increases the manufacturing cost.
Furthermore, to avoid a rigidity loss of the ball joint which may occur when the parts have been assembled with a play, the ball seat c is often pressed into the housing a. This may result in unevenness of various dimensions such as an inner diameter of the housing a and inner and/or outer diameters of the ball seat c, which may cause, in turn, the rotatable and tiltable performances desired for the ball joint to be deteriorated. Particularly, welding the rod b to the housing a is liable to distort the housing a.